#ifndef __priorityq_h_
#define __priorityq_h_

/*
** License Applicability. Except to the extent portions of this file are
** made subject to an alternative license as permitted in the SGI Free
** Software License B, Version 1.1 (the "License"), the contents of this
** file are subject only to the provisions of the License. You may not use
** this file except in compliance with the License. You may obtain a copy
** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
** 
** http://oss.sgi.com/projects/FreeB
** 
** Note that, as provided in the License, the Software is distributed on an
** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
** 
** Original Code. The Original Code is: OpenGL Sample Implementation,
** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
** Copyright in any portions created by third parties is as indicated
** elsewhere herein. All Rights Reserved.
** 
** Additional Notice Provisions: The application programming interfaces
** established by SGI in conjunction with the Original Code are The
** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
** Window System(R) (Version 1.3), released October 19, 1998. This software
** was created using the OpenGL(R) version 1.2.1 Sample Implementation
** published by SGI, but has not been independently verified as being
** compliant with the OpenGL(R) version 1.2.1 Specification.
**
*/
/*
** Author: Eric Veach, July 1994.
**
** $Date: 2001/03/17 00:25:41 $ $Revision: 1.1 $
** $Header: /cvs/mesa/Mesa/src/glu/sgi/libtess/priorityq-heap.c,v 1.1 2001/03/17 00:25:41 brianp Exp $
*/

namespace Tess
{

typedef void *PQKey;
typedef int PQHandle;

typedef bool (*compareCallback)(PQKey key1, PQKey key2);

class PriorityQ
{
public:

    PriorityQ(compareCallback pfnCallback);
    ~PriorityQ();

    void Init();

    PQHandle Insert(PQKey key);

    PQKey ExtractMin();

    void Delete(PQHandle handle);

    PQKey Minimum() { return m_handles[m_nodes[1].handle].key; }
    bool IsEmpty() { return m_size == 0; }


private:

    void FloatDown(int curr);
    void FloatUp(int curr);

    typedef struct { PQHandle handle; } PQNode;
    typedef struct { PQKey key; PQHandle node; } PQHandleElem;

    PQNode *m_nodes;
    PQHandleElem *m_handles;

    int		m_size, m_max;
    PQHandle m_freeList;
    bool m_isInitialized;
    static const int c_initSize = 32;

    compareCallback m_pfnCallback;
};

} // namespace Tess

#endif
